I'd like to inform the ECOLOG community about sets of questions
focusing on energy and matter (carbon) that have been validated by
extensive education research. Called Diagnostic Question Clusters
(DQCs), the questions, theoretical foundation, and pedagogical
suggestions are on our website "Thinking Like a Biologist"
(www.biodqc.org/). This work has been funded by several NSF grants.
Andy Anderson, Laurel Hartley, Brook Wilke, and other members of the
research team have worked together to develop and validate the DQCs
First, what the questions are not. They are not test questions and
certainly shouldn't be used on exams. These multiple
choice/true-false and open response questions are based on interviews
and analysis of extended responses with large numbers of university
students and are designed to attract students to "distracters", the
incorrect answers. (See references below for more details). Therefore
students in introductory ecology and biology courses will very likely
perform poorly.
How the questions are designed to be used: Given as short (about 15
min) pre-tests at the beginning of a course or module, the DQCs allow
faculty to better understand their students' reasoning and
understanding of energy and matter at the cellular, organismal and
ecosystem levels. ("Explain your answer" is a very important
component because students' detailed explanations much more
effectively reveal what they do/do no understand.) Then with this
information faculty can focus on essential ideas students aren't
getting, ideally including some active-learning activity (examples
are on the website). The next step is the post-test (matched with the
pre-test) which shows faculty (and students) whether there is an
improvement in understanding.
With the DQCs, therefore, ecology faculty actually have data based on
validated questions about their students' deep understanding of
energy and matter -before and after instruction. Faculty with large
classes can sample students' responses (10% is usually enough). We've
been working with faculty in all types of institutions across the
country; most are pretty surprised to see their students' poor
reasoning about these key ecological and biological processes, even
at the end of their courses.
An example: For one DQC question students are shown the Keeling Cure,
including an insert depicting an annual cycle, and asked "Why do you
think this graph shows atmospheric carbon dioxide levels decreasing
in the summer and fall every year and increasing in the winter and
spring?" Most introductory students make a vague connection between
the interannual cycle and plants, but when asked to explain this few
mention photosynthesis and even fewer respiration - nevermind explain
why. Therefore, these students do not connect these two central
cellular/organismal processes with ecosystem-level C dynamics (even
on non-global scales). This question is in the DQC-cluster titled
"Keeling Curve" and its match for the post test is called "BioFuels"
(see table at biodqc.org/dqcs).
Clearly, there is a lot to say about all of this. Please email me
with any questions you have.
D'Avanzo. C. 2008a. Biology concept inventories: overview, status,
and next steps. BioScience 58 (11): 1079-1085
Wilson, CD, CW Anderson, M Heidemann, JE Merrill, BW Merritt, G
Richmond, DF Sibley, & JM Parker. 2006. Assessing students' ability
to trace matter in dynamic systems in cell biology. CBE Life Sciences
Education 5: 323-331
--
Charlene D'Avanzo
Professor of Ecology &
Director, Center for Teaching and Learning
Hampshire College
TIEE: tiee.ecoed.net
